Feeding chute for metal powder rolling mill



-' Jan. 5, 1 960 F. K. ROEMER 2,919,466

FEEDING CI-IUTE FOR METAL POWDER ROLLING MILL Filed Oct. 22, 1958 2 Sheets-Sheet 1 INVENTOR. FRANZ K. RD E MER BY 0% f/ I HIS ATTORNEY.

Jan. 5, 1960 F. K. ROEMER FEEDING CHUTE FOR METAL POWDER ROLLING MILL Filed Oct. 22, 1958 2 Sheets-Sheet 2 FIG. 3

FIG.

INVENTOR. FRANZ K. ROEMER BY W /MQ HIS ATTORNEY.

United States FEEDING CHUTE FOR METAL POWDER ROLLING MILL Application October 22, 1958, Serial No. 768,919

Claims. (Cl. 18-9) This invention relates to a feeding chute for metal powder rolling mills and has particular relation to a structure for producing a well defined straight edge on either side of the rolled strip.

Many types of rolling mills have been devised and made for converting metallic powder into rolled strip. This process of compacting the powder comprises the compressing of metallic powder into a desired strip, and the strip may later be sintered in a furnace.

If powder is to be compacted by this method the most convenient means of compacting is to employ a set of heavy duty pressure rollers journaled in stout bearings and set close together and turned by suitable power means. The metallic powder is fed into a chute which deposits the powder in the space between the rollers. As the rollers revolve the powder is compressed into strip form which may be used in a variety of ways.

While this process is convenient and useful in producing strip metal of any desired length by compacting the iron powder, the rolling process has always had the disadvantage of producing an irregular edge to the strip and consequently a lack of uniform density across the strip.

The present invention produces a rolled strip from metallic powder which has relatively straight edges, the width of which is limited only by the width of the chute. In addition, the structure as hereinafter described can be easily adapted to produce strips having a uniformity of density across their full width and the strips can be made of varying width, this change in width being produced by a simple mechanical adjustment.

The invention utilizes the usual rolls and a novel chute with a plurality of guide plates on either side of the chute accurately fitted to the roller surfaces and resting on the rolls. These plates are loosely held in place by a pocket at either side of the chute. The two rollers in side view thus form on their upper inner peripheries a pair of curved shoulders and the guide plates ride on these shoulders and extend down into the space where the powder undergoes its greatest compression. The plates, however, are not drawn into the space between the rolls because they are formedwith arcuate lower edges which ride on the top of the rollers which keep them in position.

One of the objects of this invention is to provide an improved chute for metal powder rolling mills which avoids one or more of the disadvantages and limitations of prior art arrangements.

Another object of the invention is to produce rolled strips from metallic powder having a more uniform density entirely across the strip than is achieved with prior arrangements.

Another object of the invention is to conserve the powdered material used when producing rolled strips by producing a straight edge and with a remarkably small amount of loose powder.

Another object of the invention is to reduce the cost of rolled strips by eliminating subsequent cutting action atent O along the longitudinal edges of the strip to produce the desired width.

In accordance with the present invention the chute comprises a pair of spaced, inwardly inclined side walls whose lower edges, which are parallel with the axes of the compacting rollers, lie at points spaced upwardly and outwardly from the nip of said rollers, and a pair of end walls extending down into the gap between the rollers, each of said end walls being provided with a pocket receiving a plurality of loosely held, thin plates of soft metal, plastic, paper or other suitable material in order to prevent the spreading or escape of powder beyond the intended width of the strip.

All of the devices of the prior art had single end plates which, even if exactly machined and fitted into the gap between the rollers, did not succeed in limiting the side spreading of powder beyond the intended width of the strip. Experience has shown that metal powder of fine particle size will escape sidewise through the inevitable tiny openings between the end plates and the rollers, especially deep down in the gap between the rolls in little shavings at the sides.

Where a machined point can hardly be maintained. As a result of this, the rolled strip or band which comes out does not have edges which are sharply limited but rather are fringed and loose as compacted powder passes out As a result of this the density of the rolled strip near the edge is lower and the effect of compacting the powder is impaired.

For a better understanding of the present invention, together with other and further objects thereof, reference is made to the following description taken in connection with the accompanying drawings.

Fig. l is a side view of the rolls and chute with some parts in section, this view being taken along line 11 of Fig. 2.

Fig. 2 is a top view of the rolls and chute with some parts broken away.

Fig. 3 is a cross sectional view taken along line 3--3 of Fig. 2.

Fig. 4 is a side view of one of the guide plates.

A chute embodying the present invention includes a I pair of opposed side plates 10 which are downwardly and inwardly inclined and Whose lower ends 11 are disposed at points spaced from the nip of the compacting rollers 12. The construction of the rollers is well known and they are provided with trunnions 13 at their opposed ends which are received in anti-friction bearings (not shown).

The side walls 10 are guided at their opposed ends in milled slots 14 in the end plates 15 and supported by ears 35 extending through the end walls. The end walls are supported in their spaced relation by means of distance rods 16 having heads at one end thereof and nuts at their opposite ends. When a strip of greater width is to be made the side plates 10 are removed by loosening the nuts on the distance rods, removing the plates, and inserting wider ones in their places in slots 14.

There is shown at 20 in Fig. 3 two spaced walls forming part of the rolling mill frame, and cross bars 21 connect opposed ends of these walls where they are secured by bolts 22.

A block 23 acting as additional spacer between end plates 15 is secured midway between the ends of each cross-bar 21 by means of bolts 24. The end plates 15 with their milled slots 14 to receive the side walls 10 are fastened down to the cross bars 21 by means of top plates 36, and when a wider strip is to be rolled the end walls 15 occupy a position further apart than is shown in Figs. 2 and 3.

The important feature of the present invention is the end wall structure featuring, as it does, pockets 25 mounted on the outer faces of end plates 15 which carry in loose-fit relation a plurality of thin plates 26. It will be noted from Fig. 1 that the lower edge of each end wall is substantially V-shaped with two arcuately shaped, concave edge sections 30 conforming with the shape of the opposed shoulders 31 of the compacting rollers but which are spaced slightly from said shoulders.

Each plate 26 may be about .020 inch in thickness and may be formed from any of the materials previously mentioned although the metal plates appear to give the best results. Of the metals, sheet brass has given especially good results. They are initially formed with substantially l-shaped lower edges 32 which intersect at point 33 deep in the recess between the compacting rollers.

The pockets 25 are formed with narrow end walls 34 whose inner faces are spaced apart a distance a little greater than the width of the plates 26 in order to assure somewhat loose mounting of the plates in the pockets. Also the distance between the outer face of end wall 15 and the inner face of the pocket is slightly greater than the combined thickness of all the plates being used.

During operation of the apparatus the previously formed lower V-shaped edges 32 of barrier plates 26 tend to be ground to greater accuracy relative to the shoulders 31 of the rollers and each of the loosely fitting plates forms a separate barrier so that if a few of the powder particles somehow manage to pass the first barrier plate they will most probably be stopped by the second plate. Rarely, if ever, will the finely divided powder particles get past the last plate.

The number of barrier plates is, of course, a matter of choice but two or more are necessary and seven or eight are preferred. The metal powder is fed by gravity to the interior of the chute (if desired suitable agitation for insuring proper flow of the powder and preventing arching at the corners may be provided) and thence, by gravity and friction, taken in by the rollers.

While there have been described herein what are at present considered preferred embodiments of the invention, it will be obvious to those skilled in the art that many modifications and changes may be made therein without departing from the essence of the invention. It is therefore to be understood that the exemplary embodiments are illustrative and not restrictive of the invention, the scope of which is defined in the appended claims, and that all modifications that come within the meaning and range of equivalency of the claims are intended to be included therein.

What I claim is:

l. A feeding chute for a metal powder rolling mill provided with a pair of juxtaposed compacting rollers,

said chute comprising a pair of spaced, inwardly inclined side Walls whose lower edges terminate inside the up per peripheries of the adjoining rollers, 21 pair of spaced end walls extending downwardly into the gap between the rollers, and a plurality of barrier plates loosely mounted on the faces of each end wall and whose lower edges are substantially V-shaped and conform to the contour of the gaps between the rollers, said plates acting as barriers to resist flow of the metal powder outwardly along the rollers from the interior of the chute.

2. The combination with a metal powder rolling mill having pairs of juxtaposed rollers for compacting the powder into strip form, of a feeding chute positioned above the rollers and comprising a pair of spaced side walls for delivering powder to the gap between the rollers, and end walls carried by the side walls, and a plurality of super-imposed barrier plates loosely mounted on one face of each end wall and whose lower edges conform to the substantially V-shaped shoulders of the rollers and which contact the peripheries thereof to prevent sidewise travel of the metal particles out of the chute.

3. The combination with a metal powder rolling mill having pairs of juxtaposed power driven rollers for compacting the powder into strip form, of a feeding chute positioned above the rollers and comprising a pair of spaced side walls for delivering powder to the gap between the rollers, and end walls limiting the width of the strip, each end wall having a pocket mounted in its outer face and a plurality of barrier plates mounted in said pocket and whose lower edges conform to the substantially V-shaped shoulders of the rollers and which contact the peripheries thereof to prevent sidewise travel of the metal particles out of the chute, the barrier plates being freely movable upwardly in said pockets.

4. A feeding chute for a metal powder rolling mill I provided with a pair of juxtaposed compacting rollers,

said chute comprising a pair of spaced, inwardly inclined side walls and a pair of spaced end walls extending downwardly into the gap between the rollers, each end Wall having a pocket on its outer face and a plurality of barrier plates whose lower edges are substantially V-shaped and conform to the contour of the gap between the rollers, loosely mounted in each pocket and acting as a barrier to resist flow of the metal powder outwardly along the rollers from the interior of the chute.

5. The combination with a metal powder rolling mill having pairs of juxtaposed rollers for compacting the powder into strip form, of a feeding chute positioned above the rollers and comprising a pair of spaced side walls for delivering powder to the gap between the rollers, and end walls limiting the width of the strip, each end wall having a pocket associated with one face thereof and a plurality of barrier plates loosely mounted in the pocket and whose lower edges conform to the substantially V-shaped shoulders of the rollers and which contact the peripheries thereof to prevent sidewise travel of the metal particles out of the chute.

References Cited in the file of this patent UNITED STATES PATENTS 615,298 Mullen et al. Dec. 6, 1898 1,277,729 Kearns Sept. 3, l9l8 1,566,771 Perry Dec. 22, 1925 1,575,213 Kohler Mar. 2, l926 1,664,273 Theroux Mar. 27, 1928 1,893,937 Gardiner Jan. 10, 1933 

